Typical conventional foldable tent frames, such as disclosed in U.S. Pat. Nos. 6,397,872, 6,431,193, and 6,470,902, issued to Carter and U.S. Pat. No. 5,638,853, issued to Tsai, use one or more X-shaped connectors to form scissors assemblies to connect between four leg posts. The scissor assemblies can expand and contract between the leg posts thereby expanding the distance between the posts out to a maximally expanded deployed position. Typically, each scissors assembly is attached to fixed brackets or angles disposed on the top ends of the corresponding leg posts and is attached to movable, sliding brackets or angles disposed to slide along the corresponding leg posts. In this manner, each scissor assembly may expand or contract by pulling the leg posts away from, or towards, each other respectively because each scissor assembly is fixed to the top of its corresponding leg posts and is secured to move with the sliding brackets also on the corresponding leg posts. The roof structure disclosed in U.S. Pat. No. 6,397,872 is attached to the scissor assemblies and is configured to expand as the scissor assemblies expand between the leg posts. Central scissor assemblies are connected to the center of the peripheral scissor assemblies (i.e., the scissor assemblies connecting adjacent leg posts) so that the central scissor assemblies unfold as the peripheral scissor assemblies are moved into the expanded state. The central scissor assemblies are made using X-shaped connectors in a manner similar to how the peripheral scissor assemblies are constructed. At the same time as the peripheral and central scissor assemblies are expanded, a central support member is raised into its vertical supporting position and has an extendable vertical peak pole member that is used to support a tent canopy and provide a peak for the tent canopy.
With the conventional foldable tent frame, once the tent is completely unfolded into its fully expanded or deployed position, the roof forms an angular pyramid or triangular shape (i.e., a “A” shape). One drawback of such conventional foldable tent roof structures is that the configuration requires a center post, or central support member, and several central scissor assemblies connected together to lift the center post, or central support member, upwards into its vertically extended or deployed position. These added structures add to the overall weight of the tent frame, and the cost to manufacture such a tent frame is inevitably increased. Moreover, because the roof invariably forms an angular pyramid or triangular shape (i.e., a “A” shape), extra installation speed (i.e., height) is required. Lastly, the protruding top or center post is likely to be affected by strong winds.
To overcome this structural drawback, several roof structure configurations have been constructed such as disclosed in U.S. Pat. Nos. 6,431,193, 6,470,902 and 5,638,853 that avoid the use of central scissor assemblies and the central support member. However, the trade off is that these roof structures are relatively flexible and flimsy, which means that these structures tend to collapse in strong winds or have profiles that are lowered. For example, the collapsible shelter with flexible collapsible canopy disclosed in U.S. Pat. No. 6,431,193 (“Carter '193 Patent”) has a flexible roof structure provided by four segmented flexible poles connected together at one end by a central hub member and connected at the opposite end to the scissors assembly (“perimeter truss pairs”) of the perimeter framework. With the roof structure erected into its extended position, the roof structure can flex between an upper convex position and a lower concave position while the perimeter truss pairs are in an extended position. This Carter '193 Patent also teaches that because the roof structure is flexible, it collapses during strong winds or that its profile is lowered. However, there is a demand for lightweight tent structures that have reinforced, lightweight roof structures that avoids this flexible, collapsible feature because many consumers do not want a tent with a roof that will collapse or lower its profile in strong winds.
The Carter '193 Patent is the most recent member of a patent firmly that includes the following patents: U.S. Pat. No. 5,511,572, (“Carter '572 Patent”), U.S. Pat. No. 5,632,293 (“Carter '293 Patent”), U.S. Pat. No. 5,797,412 (“Carter '412 Patent”), U.S. Pat. No. 5,921,260 (“Carter '260 Patent”), U.S. Pat. No. 6,076,312 (“Carter '312 Patent”), and U.S. Pat. No. 6,240,940 (“Carter '940 Patent”). Various disadvantageous features of these patents are not present in the present invention.
The Carter '572 Patent claims a plurality of clip members for removably receiving pole members. The present invention does not have this feature. The drawback of the canopy disclosed by Carter '572 Patent is that flexible, collapsible pole members must be inserted into the clip members when collapsed, which adds to the complexity of storing and deploying the canopy.
The Carter '293 Patent claims a flexible, collapsible canopy movable between a normal raised position and a lowered position when the perimeter truss pairs are in the extended position. FIGS. 8 and 17 of the Carter '293 Patent illustrate this feature. The roof structure for a folding tent frame in accordance with the present invention does not have the ability to flex and collapse while the truss structure is in the extended position. As mentioned above for the Carter '193 Patent, the drawback of the canopy of the Carter '293 patent is that the canopy may flex into the lowered position during strong winds, thereby striking or otherwise interfering with people taking shelter underneath the canopy.
The Carter '312 Patent claims a flexible, collapsible canopy wherein the flexible, collapsible canopy is movable from a normal raised position to a lower position when the perimeter truss pairs of link members are in the second position, thereby providing the collapsible shelter with a reduced profile when a portion of elongated members is in the lower position. FIGS. 8 and 17 of the Carter '312 Patent illustrate this flexible, collapsible feature of the Carter canopy; however, the roof structure of the folding tent frame in accordance with the present invention does not have this feature because the roof cannot flex and collapse when the supporting truss assembly is in the extended position. As mentioned above for the Carter '912 Patent, the drawback of the canopy of the Carter '312 patent is that the canopy may flex into the lowered position during strong winds, thereby striking or otherwise interfering with people taking shelter underneath the canopy.
The Carter '940 Patent claims a flexible canopy being flexible and movable from a normal raised position to lower positions when the perimeter truss pairs are in the second extended position, thereby providing the collapsible shelter with a reduced profile when at least a position of elongated members of the canopy are in lower positions. FIG. 17 of the Carter '940 patent shows this claimed feature as a partially collapsed canopy when wind blows thereon even though the perimeter truss pairs are in the extended position. As discussed above, the roof structure in accordance with the folding tent structure of the present invention does not have this feature. As mentioned above for the Carter '193 Patent, the drawback of the canopy of the Carter '940 patent is that the canopy may flex into the lowered position during strong winds, thereby striking or otherwise interfering with people taking shelter underneath the canopy.
To avoid the drawbacks of tent structures having flexible, collapsible roof structures similar to those disclosed and claimed in the Carter '293 Patent, for example, others have developed relatively inflexible reinforced roof structures such as disclosed in U.S. Pat. No. 6,470,902 (“Carter '902 Patent”) to Carter and U.S. Pat. No. 5,638,853 (“Tsai Patent”) to Tsai. Generally, these tent structures have roof structures provided by four pole members connected to a central hub at one end and to the perimeter scissors assembly at the other end. The four pole members are segmented, each pole member having a joint or hinge between two pole segments so as to fold or pivot about the joint or hinge whenever the roof structure moves between collapsed and extended positions. To prevent the four pole members from having the type of flexibility in the extended position as described in the Carter '293 Patent a support strut member is provided for each of the four pole members. Each support strut member is connected at one end to the lower one of the pole segments of the corresponding pole member and at the other end to the movable, sliding bracket or angle disposed to slide along the corresponding leg of the perimeter scissors assembly. The support strut members reinforce the roof structure so as to prevent the pole members from flexing or collapsing while the roof structure and the perimeter scissors assembly are in the extended position. Thus, roof structures such as disclosed in the Carter '902 Patent and the Tsai Patent do not have the feature of the Carter '293 Patent, wherein the roof structure flexes between an upper convex position and a lower concave position while the perimeter truss pairs are in an extended position.
Despite this added strength, roof structures of the kind disclosed in the Carter '902 Patent and the Tsai Patent have several drawbacks. First, the shape of the roof structure approximates an angular pyramid or triangular shape, which has a limiting effect on the amount of headroom provided under the canopy placed on the roof structure. A roof structure that more closely approximates a circular dome shape would provide more head room for a given height of the peripheral scissors assembly. Furthermore, a roof structure that more closely approximates a dome shape would provide an aesthetically pleasing look that has not yet been achieved in the art of portable folding tent or canopy structures utilizing scissor truss assemblies. In addition, the tent frame made in accordance with the present invention does not have the strut members mounted on a shaft between adjacent pair of link members as disclosed in the Carter '902 Patent. This structure of the Carter '902 Patent has the drawback of unnecessarily complicating the manufacture of the canopy without a substantial benefit.
The roof structure disclosed by the Tsai Patent is less complicated than the Carter '902 Patent. However, the tent structure disclosed by the Tsai Patent includes a cumbersome and specialized hinge (“intermediate pivot connecting member”) between the first and second rod members that form the roof structure. Specifically, this specialized hinge includes a pair of opposing pivot members spaced above a board member. The present invention does not use this kind of a specialized hinge. The tent structure in accordance with the present invention utilizes a protruding hinge instead of that an upper pole is connected to a central pole, and a support pole assembly is then connected to both the upper pole and the central pole using other protruding hinges. In this manner, the tent structure in accordance with the present invention provides a gentle roof curve when deployed as will be described in detail below.
Therefore, it is an object of the present invention to provide a new foldable lightweight tent frame having a simple structure that can form a gentle roof curve with the center protruding upward by unfolding the peripheral scissors assembly and deploying the leg posts.
It is another object of the present invention to provide a configuration of a foldable tent structure wherein the roof is deployed as it extends upward as the leg posts are deployed and the peripheral scissor assembly unfolds, thereby offering a new type of frame that allows a plurality of poles, which are relatively thin and elastic enough to bow or bend a little, to form a roof as the leg posts are deployed and the peripheral scissor assembly unfolds.
It is another object of the present invention to provide a foldable tent structure having a roof structure that more closely approximates a convex circular dome shape to provide more head room for a given height of the peripheral scissors assembly.
It is another object of the present invention to provide a foldable tent structure having a roof structure that more closely approximates a circular dome shape to provide a new pleasing aesthetic look previously not achieved in portable, foldable tent structures.
It is another object of the present invention to provide a foldable tent structure that is easy and cost effective to manufacture.
It is another object of the present invention to provide a foldable tent structure that is durable and easy to clean and maintain.